JP6627084B2 - Insulated containers and structures - Google Patents

Description

  The present invention relates to a heat insulating container and a heat insulating structure such as a low temperature tank for storing an ultra low temperature substance such as LNG (liquefied natural gas).

  As a typical thing for storing ultra-low temperature materials such as Liquid Natural Gas (LNG), there is an LNG transport ship. There are two types of LNG carriers: independent tank type and membrane type. The membrane type includes a primary sealing wall and a secondary sealing wall, and a heat insulating wall. The heat insulating wall is generally configured by filling a box such as a plywood with a heat insulating material such as perlite or glass wool. Since the heat insulating wall needs to maintain an ultra-low temperature substance such as LNG at about -162 ° C, the higher the heat insulating property, the better.

  Therefore, in order to enhance the heat insulating property of the heat insulating container holding the ultra-low temperature material, although not a heat insulating container for an LNG transport ship, a vacuum heat insulating member is provided between the inner tank and the outer tank together with heat insulating material such as perlite. A provided low-temperature tank has been proposed (for example, see Patent Document 1).

  FIG. 10 is a view showing a conventional heat insulating structure of a low-temperature tank shown in Patent Document 1. As shown in FIG.

  As shown in FIG. 10, the heat insulating structure of the low-temperature tank includes an inner tank 101 and an outer tank 102. In addition, a vacuum ball 103 filled between the inner tank 101 and the outer tank 102 and a powder heat insulating material 104 such as pearlite filled between the inner tank 101 and the outer tank 102 are provided. I have.

  According to such a configuration, a vacuum region can be created in the powder heat insulating material 104 between the tank inner tank 101 and the tank outer tank 102 (in a non-vacuum heat insulating structure). And the heat insulation performance can be improved by the amount of this vacuum region.

  However, in the above-described conventional configuration, the heat insulating property is improved by the provision of the vacuum region, but the vacuum sphere 103 becomes extremely low temperature due to the ultra-low heat of the LNG or the like in the tank 101 inside the tank. In particular, since the vacuum sphere 103 on the tank inner tank 101 side has an extremely low temperature, the vacuum sphere 103 needs to be formed of a metal that can withstand this ultra-low temperature, and has a special configuration with no versatility, resulting in high cost. .

  It is assumed that this configuration is applied to a heat insulating wall of an LNG transport ship, that is, a box such as a plywood is filled with a vacuum bulb 103 together with a heat insulating material such as perlite to form a heat insulating wall. In this case, the cost increase of each heat insulation wall is accumulated for several thousands of heat insulation walls to be used, and when summed up, the cost increase rate becomes extremely high, realizing the configuration in reality. It was difficult to do.

JP-A-7-190297

  The applicant tried to perform vacuum heat insulation using a panel-shaped vacuum heat insulating material, which is available as a general-purpose product, instead of the vacuum sphere of Patent Document 1.

  Since this panel-shaped vacuum heat insulating material is a general-purpose product, it is inexpensive, and it is possible to realize significant suppression of cost increase. However, during long-term use, perlite or the like, which is a heat insulating material filled in a box such as a plywood board, becomes thin, and a play gap is generated between the vacuum heat insulating material in the box and the inside of the box. Due to the play gap, the vacuum heat insulating material vibrates slightly with the vibration of the LNG hull, and the outer cover material rubs against the inner surface of the box and is damaged. There are signs of decline.

  In particular, since the ultra-low temperature of the material such as LNG which is conducted through the heat insulating material such as pearlite leaks from the outer material of the vacuum heat insulating material, the multilayer laminated film which is the outer material of the vacuum heat insulating material tends to be low-temperature embrittlement. It is in. For this reason, it is necessary to devise a method of providing the vacuum heat insulating material.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a heat insulating container and a heat insulating structure capable of ensuring high heat insulating performance over a long period of time while realizing cost reduction.

  The insulated container of the present invention is an insulated container that holds a substance at least 100 ° C. lower than room temperature, and includes an inner container, an outer container, and an insulated box provided between the inner container and the outer container. And a heat insulating layer provided inside the heat insulating box. And the heat insulating layer has a panel-shaped vacuum heat insulating material having a core material and a jacket material for vacuum-sealing the core material, and a heat insulating material made of a material different from the vacuum heat insulating material. I have. Further, the vacuum heat insulating material has a thermal stress dispersion layer and is fixed to the heat insulating box.

  Further, the heat insulating structure of the present invention is a heat insulating structure provided with an outer container, a first heat insulating box, and a second heat insulating box. The first heat insulating box includes a first box frame, a first heat insulating material provided in the first box frame, and a first closing plate closing an opening side of the first box frame. Has been unitized. The second heat-insulating box is provided on the second box frame, a partition provided in the second box frame, and partitioning the inside of the second heat-insulating box, and laid on a bottom surface of a section partitioned by the partition. It is unitized by a vacuum heat insulating material, a second heat insulating material arranged on the opening side of the vacuum heat insulating material, and a second closing plate closing the opening side of the second box frame. And the 2nd heat insulation box is arrange | positioned at the container outer tank side rather than the 1st heat insulation box, The vacuum heat insulating material has a thermal stress dispersion layer, and is being fixed to the 2nd closing plate.

  With such a configuration, it is possible to use a general-purpose panel-shaped vacuum heat insulating material to secure the heat insulating property at a low cost, and even if the heat insulating material in the heat insulating box becomes thin and a play gap is formed, the vacuum heat insulating material is used. The material does not vibrate minutely in the heat insulating box, and the heat insulating property can be prevented from lowering due to the damage of the covering material. Therefore, it is possible to prevent a decrease in heat insulation performance due to damage to the outer cover material of the vacuum heat insulation material, and to ensure high heat insulation over a long period of time at low cost.

  As described above, according to the present invention, it is possible to provide a heat insulating container and a heat insulating structure that can ensure high heat insulating performance at a low cost over a long period of time.

FIG. 1 is a sectional view of the heat insulating container according to the first embodiment of the present invention. FIG. 2 is a schematic diagram showing the internal structure of the heat insulating structure used for the heat insulating container according to the first embodiment of the present invention. FIG. 3 is a perspective view of a heat insulating structure used for the heat insulating container according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view of the vacuum heat insulating material used for the heat insulating structure used for the heat insulating container according to the first embodiment of the present invention. FIG. 5 is a plan view of a vacuum heat insulating material used for the heat insulating structure used for the heat insulating container according to the first embodiment of the present invention. FIG. 6 is an explanatory diagram illustrating a thermal simulation result of the heat insulating container according to the first embodiment of the present invention. FIG. 7 is a diagram showing an experimental example according to the first embodiment of the present invention. FIG. 8 is a sectional view showing a heat insulating structure of a heat insulating container according to the third embodiment of the present invention. FIG. 9A is a diagram illustrating an example of a configuration of an explosion-proof structure according to a fourth embodiment of the present invention. FIG. 9B is a diagram illustrating another example of the configuration of the explosion-proof structure according to the fourth embodiment of the present invention. FIG. 10 is a view showing a conventional heat insulating structure of a low-temperature tank shown in Patent Document 1. As shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited by each embodiment.

(First Embodiment)
1 to 5 show the configuration of the heat insulating container 1 according to the first embodiment.

  FIG. 1 is a cross-sectional view of the heat insulating container 1 according to the first embodiment of the present invention, FIG. 2 is a schematic diagram showing an internal structure of a heat insulating structure used in the heat insulating container 1, and FIG. FIG. 4 is a perspective view of the heat insulating structure, FIG. 4 is a sectional view of a vacuum heat insulating material 9 used in the heat insulating structure, FIG. 5 is a plan view of the vacuum heat insulating material 9, and FIG. It is explanatory drawing which shows the heat simulation result of the heat insulation container 1 in the 1st Embodiment.

  In the present embodiment, a configuration in the case of a membrane system in which the hull itself is used as the heat insulating container 1 such as an LNG transport ship is shown.

  As shown in FIG. 1, the heat-insulating container 1 is constituted by the hull itself, and employs a double heat-insulating structure called a primary heat-insulating and a secondary heat-insulating inside a container serving as a tank. Have been.

  As shown in FIGS. 2 and 3, the heat insulating container 1 includes a container outer tank 2, an intermediate tank 4 provided inside the container outer tank 2, and a container inner tank provided via the intermediate tank 4. 3 is provided. Both the container inner tank 3 and the intermediate tank 4 are made of a stainless steel membrane or invar (nickel steel containing 36% nickel), and have a structure that is strong against heat shrinkage.

  The first heat-insulating box 5, which is a heat-insulating structure disposed between the vessel inner tank 3 and the intermediate tank 4, is made of a wooden box frame 6 (first box frame) such as a veneer plate having an open surface. And a powder heat insulating material 7 (first heat insulating material) such as pearlite filled in the box frame 6. Note that the first heat insulating material may be made of glass wool or the like instead of pearlite. In the present embodiment, the case where pearlite which is the powder heat insulating material 7 is used as the first heat insulating material will be described. .

  Like the first heat insulating box 5, the second heat insulating box 8 disposed between the intermediate bath 4 and the container outer bath 2 has a wooden box frame 6 (a second box frame) having an open side. A material having a lower thermal conductivity λ than the powder heat insulating material 7 on the bottom surface of the body, in this embodiment, a thermal conductivity of 0.002 W / (m · K) at 0 ° C., which is about 20 times that of pearlite. It is constituted by laying a vacuum heat insulating material 9 which is as low as possible. The opening side portion is filled with a powder heat insulating material 7 (a second heat insulating material) such as perlite, similarly to the first heat insulating box 5, and is configured.

  In the present embodiment, when forming the heat insulating box, the inside of the box frame 6 is divided into a plurality of sections by the partition 6a, and the plurality of sections are filled with the powder heat insulating material 7, and then the box frame is formed. The unit is formed by closing with a closing plate 10 made of the same material as 6. By arranging this unit, the first heat insulation box 5 and the second heat insulation box 8 are constructed.

  Here, the second heat insulating box 8 is arranged so that the vacuum heat insulating material 9 faces the outside, that is, the container outer tank 2 side. Therefore, the powder heat insulating material 7 of the first heat insulating box 5 and the second heat insulating box 8 forms a first heat insulating layer on the low temperature side, and the vacuum heat insulating material 9 forms a second heat insulating layer. It will be.

  FIG. 4 shows a vacuum heat insulating material 9 serving as a second heat insulating layer.

  As shown in FIG. 4, the vacuum heat insulating material 9 is formed in a panel shape by enclosing the core material 11 in the outer cover material 12 and sealing it under reduced pressure. The outer cover material 12 includes a first protective layer 13a made of a pet film having a thickness of 12 μm, a second protective layer 13b made of a nylon film having a thickness of 25 μm, a gas barrier layer 14 made of aluminum foil having a thickness of 7 μm, This is a laminated film in which a heat-welding layer 15 made of a low-density polyethylene film having a thickness of 50 μm and a multi-layered structure.

  The vacuum heat insulating material 9 decompresses the core material 11 having an average fiber diameter of 4 μm and formed by firing glass fiber formed by centrifugal method, and the adsorbent 16 mainly composed of calcium oxide. In this case, the heat-welding layers 15 are thermally bonded so as to be opposed to each other and sealed. A sealing fin 17 in which the core material 11 is not inside and the outer covering materials 12 are in contact with each other is formed in the heat-welded portion and an outer portion therefrom.

  Further, in the vacuum heat insulating material 9 of the present embodiment, the thermal stress dispersion layer 18 is laminated and integrated on the outer sides of the pet film of the first protective layer 13a constituting the outer cover material 12, respectively. . That is, the outermost layer of the jacket material 12 is constituted by the thermal stress dispersion layer 18. The thermal stress dispersion layer 18 may be integrated with the first protective layer 13a by bonding.

  The thermal stress dispersing layer 18 is formed of a material having a small linear expansion coefficient and a small thermal shrinkage, and having high resistance to ultra-low temperatures and high mechanical strength. For example, in the present embodiment, the thermal stress dispersion layer 18 is formed by a glass cloth having a thickness of about 150 μm.

  Further, in the present embodiment, the vacuum heat insulating material 9 is provided with a thermal stress distribution layer 18 of the outer cover material 12, and in this embodiment, the closing plate 10 (second Is closed by an adhesive such as hot melt.

  Further, as the gas adsorbent contained in the adsorbent 16 of the vacuum heat insulating material 9, a powdery adsorbent made of ZSM-5 type zeolite having a large surface area is used. In addition, in order to improve the nitrogen adsorption characteristics at room temperature, among the ZSM-5 type zeolites, more preferably, at least 50% or more of the copper sites of the ZSM-5 type zeolite are copper monovalent sites. Yes, an adsorbent in which at least 50% or more of the copper monovalent sites are oxygen tricoordinate copper monovalent sites can be used.

  As described above, by using the gas adsorbent in which the ratio of the oxygen trivalent copper monovalent site is increased, the amount of adsorbed air can be significantly improved.

  The gas adsorbent used in the present embodiment is a ZSM-5 type zeolite, which is formed without using a combustible material. As a result, when the gas adsorbent is disposed inside the vacuum heat insulating material used for the tank for the flammable gas such as LNG, the flammable gas has entered the inside of the vacuum heat insulating material 9 due to aging or the like. Even in this case, there is no danger of ignition or the like, and the safe vacuum heat insulating material 9 can be formed.

  Further, in the vacuum heat insulating material 9 of the present embodiment, the flame retardant structure is further improved. That is, by using inorganic fibers for the core material 11 of the vacuum heat insulating material 9, the flame retardancy is improved as compared with the heat insulating material using organic fibers, and as a result, the flame retardancy of the heat insulating container 1 can be improved. it can. Further, since the inorganic fibers are used, the volume expansion due to the moisture in the gas is small, and as a result, the shape-retaining property of the heat insulating container 1 and the explosion-proof property described later can be improved.

  Next, the operation and effect of the above-described configuration will be described.

  The heat insulating container 1 is provided with a powder heat insulating material 7 in a first heat insulating box 5 arranged on the container inner tank 3 side and a powder heat insulating material 7 in a second heat insulating box 8 located on the container outer tank 2 side. , And is insulated by the vacuum heat insulating material 9 located outside thereof, and keeps LNG in the container housing at a low temperature.

  Here, since the vacuum heat insulating material 9 is a panel-shaped general-purpose product, it can be provided at low cost, and the rate of cost increase as a heat insulating structure can be significantly reduced. Moreover, since the pearlite powder constituting the first heat insulating layer is also provided at low cost, the above-described heat insulating structure can be realized at low cost.

  The vacuum heat insulating material 9 is bonded and fixed to the closing plate 10 of the second heat insulating box 8. As a result, even if the powder heat insulating material 7 located on the container inner tank 3 side with respect to the vacuum heat insulating material 9 becomes thinner and reduced in volume due to long-term use, even if a play gap occurs in the second heat insulating box 8. In addition, the vacuum heat insulating material 9 does not vibrate minutely in the second heat insulating box 8. Therefore, it is possible to prevent the vacuum insulation material 9 from being vibrated in the second insulation box 8 due to minute vibrations, and to prevent damages such as breakage of the covering material and generation of cracks, thereby ensuring high insulation performance over a long period of time. can do.

  Further, the vacuum heat insulating material 9 is arranged outside the powder heat insulating material 7 of the second heat insulating box 8. As a result, the ultra-low temperature leaking from the ultra-low temperature substance in the container inner tank 3 to the vacuum heat insulating material 9 is first reduced by the heat insulating action of the powder heat insulating material 7, so that the low temperature embrittlement of the jacket material 12 is suppressed. Can be. Therefore, the vacuum heat insulating material 9 can maintain the original high heat insulating performance, and also suppresses the deterioration of the heat insulating performance due to the damage of the jacket material 12 due to the low-temperature embrittlement of the vacuum heat insulating material 9, and further increases the heat insulating performance. High heat insulation can be ensured over a period.

  In addition, the first heat insulating layer that insulates between the vessel inner tank 3 and the vacuum heat insulating material 9 is separated into the powder heat insulating material 7 of the first heat insulating box 5 and the powder heat insulating material 7 of the second heat insulating box 8. It is configured to be provided. Thereby, the wood of the box frame 6 and the air layer between the box frames 6 exist between them, and the physical continuity (the first heat-insulating box 5 and the second heat-insulating box 8) (Continuity in the case where the powder heat insulating material 7 is continuous from the container inner tank 3 side to the vacuum heat insulating material 9) is cut off. Thereby, the amount of heat leakage can be reduced, and the low-temperature embrittlement of the jacket material 12 of the vacuum heat insulating material 9 can be more effectively suppressed.

  Further, in the heat insulating structure of the present embodiment, the thermal conductivity λ of the vacuum heat insulating material 9 is higher than that of the powder heat insulating material 7 in the first heat insulating box 5 and the second heat insulating box 8 as described above. , About 20 times lower. Accordingly, the heat insulating performance of the vacuum heat insulating material 9 is added, so that the heat insulating performance thereof can be greatly improved as compared with the configuration including only the powder heat insulating material 7.

  Furthermore, the vacuum heat insulating material 9 makes full use of its high heat insulating performance to shut off outside heat, and the powder heat insulating material inside the vacuum heat insulating material 9, that is, in the first heat insulating box 5 and the second heat insulating box 8. The ambient temperature of the portion where the material 7 is provided is greatly reduced. Thereby, the powder heat insulating material 7 in the first heat insulating box 5 and the second heat insulating box 8 has a relatively improved heat insulating effect of the powder heat insulating material itself, and exhibits a high heat insulating effect of the vacuum heat insulating material 9 itself. Together, the heat insulation performance can be extremely high.

  FIG. 6 is an explanatory diagram showing the results of a thermal simulation in the first embodiment of the present invention. The broken line indicated by A indicates that the first heat-insulating box 5 made of the conventional pearlite powder heat-insulating material is overlapped by two. 530 mm. The dashed-dotted line indicated by B indicates characteristics of the same configuration as that of the present embodiment, including the second heat insulating box 8 having the vacuum heat insulating material 9 on the outer tank side of the first heat insulating box 5. I have.

  As is clear from FIG. 6, in the configuration of the present embodiment, the outer surface temperature of the first heat insulating layer made of the pearlite powder heat insulating material is changed from A to B by the heat insulating effect of the second heat insulating layer by the vacuum heat insulating material 9. Has been able to be reduced. That is, the atmosphere temperature of the installation portion of the first heat insulating layer is reduced by the vacuum heat insulating material 9. In addition, since the thermal gradient angle in the first heat insulating layer made of the pearlite powder heat insulating material is gentle, the transfer of low heat of the first heat insulating layer itself is reduced, and the first temperature is lowered due to the lowering of the ambient temperature. It can be seen that the heat insulating effect of the heat insulating layer is improved.

  FIG. 7 is a diagram showing an experimental example according to the first embodiment of the present invention.

  In FIG. 7, Comparative Example 1 has a configuration in which the vacuum heat insulating material 9 is not provided and only the heat insulating layer is formed. In Experimental Example 1, a change in the heat transmission coefficient was measured in a configuration in which a vacuum heat insulating material was provided as a second heat insulating layer on the outer wall side with the same heat insulating layer thickness as that of Comparative Example 1. In Experimental Example 2, when the same heat transmission coefficient as in Experimental Example 1 was used without providing the vacuum heat insulating material 9, the thickness of the heat insulating layer was measured.

  As conditions for measuring these, the temperature in the tank was -160 ° C, and the outside air temperature was 25 ° C.

  As the first heat insulating layer, a powder heat insulating material 7 such as perlite is used, and as the second heat insulating layer, a vacuum heat insulating material 9 is used.

In Experimental Example 1, the average heat transmission coefficient was measured by setting the thickness of the entire heat insulating layer in the same manner as in Comparative Example 1. In this case, the average heat transmission coefficient is, with respect to ^{0.0785 [W / m 2 · K} ] of Comparative Example 1, Experimental Example 1 ^{0.0514 [W / m 2 · K} ] , and the heat insulating performance is 35% Has improved.

  In Experimental Example 2, when trying to obtain the same heat insulating performance as in Experimental Example 1, how much the entire heat insulating layer becomes thicker was measured.

  In this case, compared to 530 [mm] of Experimental Example 1, Experimental Example 2 has a thickness of 950 [mm]. In the conventional configuration, unless the thickness is increased by 79%, the heat insulation of Experimental Example 1 as in the present embodiment is not performed. It turned out that performance could not be obtained.

  As described above, for example, by using the configuration of the present embodiment as an insulated container (tank) such as an LNG tanker that uses LNG boil-off gas as fuel, the amount of LNG used can be reduced. . Therefore, the economic efficiency is improved, and in the LNG tanker of the type that reliquefies the LNG boil-off gas, the energy loss for reliquefaction can be reduced.

  On the other hand, the vacuum heat insulating material 9 is bonded and fixed to the inner surface of the second heat insulating box 8, that is, to the closing plate 10, so that the line between the vacuum heat insulating material 9 and the material of the second heat insulating box 8, that is, the material of the closing plate 10 is formed. Due to the difference in the expansion coefficient, the multilayer laminate film which becomes the covering material 12 of the vacuum heat insulating material 9 undergoes thermal shrinkage stress accompanying the thermal shrinkage of the closing plate 10 and causes cracks during long use. Is concerned.

  That is, by bonding and integrating the vacuum heat insulating material 9 to the closing plate 10, the multilayer laminated film of the vacuum heat insulating material 9 is stretched and contracted by the heat shrinkage of the closing plate 10, and the multilayer laminated film is repeatedly stretched and contracted. A crack is generated, and there is a concern that the heat insulation performance of the vacuum heat insulating material 9 is reduced due to the crack and the heat insulation performance is reduced.

  However, in the present embodiment, the vacuum heat insulating material 9 is bonded and integrated to the closing plate 10 via the thermal stress dispersion layer 18. Therefore, it is possible to suppress the occurrence of cracks and the like in the outer cover material 12 due to the thermal contraction of the closing plate 10.

  That is, when the closing plate 10 undergoes thermal shrinkage, the tensile stretching force due to this thermal shrinkage is applied to the outer cover material 12 of the vacuum heat insulating material 9. However, the thermal stress dispersing layer 18 constituting the outermost layer of the jacket material 12 is made of glass cloth, has a small linear expansion coefficient and little thermal shrinkage, and has a resistance to ultra-low temperature and a mechanical strength. high. Thereby, the heat contraction force is dispersed and absorbed, and the heat contraction is hardly generated, while hardly causing heat contraction against the heat contraction of the closing plate 10.

  In other words, the thermal stress dispersing layer 18 exerts a tensile shrinkage force due to the thermal shrinkage of the closing plate 10 on the gas barrier layer 14 made of aluminum foil of the covering material 12 obtained by laminating and integrating the thermal stress dispersing layer 18. And the occurrence of cracks is strongly suppressed.

  In particular, thermal shrinkage cracks are likely to occur at the corners of the vacuum heat insulating material 9, but the thermal stress dispersing layer 18 receives and disperses the heat shrinkage stress that tends to concentrate at the corners, so that the thermal shrinkage cracks are dispersed. Can be protected from heat shrinkage stress, and cracks due to the concentration of the heat shrinkage stress can be efficiently suppressed.

  Therefore, even if it is used for a long time, it is possible to prevent the gas barrier layer 14 of the jacket material 12 from being cracked, maintain the high heat insulating property of the vacuum heat insulating material 9 for a long time, and maintain the heat insulating property of the heat insulating container 1. Can be guaranteed.

  In the present embodiment, a glass cloth is used as the thermal stress dispersion layer 18. Glass cloth has a small coefficient of linear expansion and low thermal shrinkage, and has high resistance to ultra-low temperatures and high mechanical strength, and also has low thermal conductivity and high heat insulation. Thereby, it is possible to suppress the low-temperature embrittlement of the jacket material 12 due to the extremely low temperature from the substance stored in the container inner tank 3. Therefore, the generation of cracks due to the low-temperature embrittlement of the jacket material 12 can be suppressed, and the heat insulation of the heat insulating container 1 can be ensured for a long period of time. In addition, flame retardancy, durability, reliability, and electrical insulation can be secured without any problem.

  Moreover, in the present embodiment, the thermal stress dispersion layer 18 which is the outermost layer of the outer cover material 12 of the vacuum heat insulating material 9 is integrally laminated on the upper and lower surfaces of the outer cover material 12, respectively. Accordingly, the outer surface of the outer cover material 12 of the vacuum heat insulating material 9 has high strength, and it is possible to prevent the outer cover material 12 from being cracked or broken by handling during production or the like. Therefore, it is possible to suppress the occurrence rate of defective products of the vacuum heat insulating material 9 which is likely to occur in the process of assembling the heat insulating structure, and to improve the heat insulating performance over a long period of time while suppressing an increase in cost.

  Further, in the configuration of the present embodiment, the vacuum heat insulating material 9 is bonded and fixed via the thermal stress dispersing layer 18 because there is a concern about cracking and bag breakage due to deterioration of the jacket material 12 due to heat shrinkage and low temperature. By devising, these problems are solved. Even if the outside air may enter the jacket material 12 for some reason, in the configuration of the present embodiment, the core material 11 formed by firing glass fiber is used. As a result, the dimensional change can be significantly suppressed as compared with the case where firing is not performed, and safety can be improved.

  For example, when the core material 11 formed by the centrifugal method is used without firing, the dimensional deformation is twice or more, and the thickness is increased to about 5 to 6 times. On the other hand, according to the configuration of the present embodiment, the dimensional deformation can be suppressed to about 1.2 times, at most 1.5 times or less, so that the dimensional deformation between the inner wall and the outer wall of the tank is reduced. It is possible to suppress the adverse effects caused by the occurrence.

  Furthermore, even if moisture remains in the outer cover material 12 of the vacuum heat insulating material 9, it is possible to prevent the core material 11 from expanding due to the moisture and from deforming the vacuum heat insulating material 9 itself. Therefore, when maintenance such as cleaning with hot water is performed periodically as in the case of an LNG heat insulating container, the vacuum heat insulating material 9 undergoes a large expansion deformation during the hot water cleaning, and the vacuum heat insulating material 9 itself undergoes a large thermal expansion deformation. Thereby, it is also possible to suppress adverse effects such as deformation of the inner wall and the outer wall of the tank.

  In the present embodiment, the core material 11 is formed by a centrifugal method. However, for example, the core material 11 formed by a papermaking method of dehydrating a water-containing core material, such as making paper, is used. It is also possible to use.

  When the core material 11 formed by the papermaking method is used, the fibers are dissolved in water in advance and the fibers are dispersed, and then dewatered, so that dimensional deformation when reduced in pressure to the atmospheric pressure is small, and the thickness is reduced. It is formed as follows. Therefore, even when the bag is broken as described above, it is possible to suppress the adverse effects caused by the dimensional deformation.

(Second embodiment)
Next, a second embodiment of the present invention will be described.

  The configuration of the second embodiment is the same as the configuration shown in FIGS. 1 to 5, except that the first protective layer 13 a and the second protective layer 13 b of the jacket 12 of the vacuum heat insulating material 9 are different. The material on the first heat insulating layer side is made of a material having higher resistance to low-temperature embrittlement than the material on the opposite side, which is in contact with the outer vessel 2.

  For example, the material of the vacuum heat insulating material 9 on the side in contact with the powder heat insulating material 7 is a material in which a laminated film is coated with aluminum foil, and the material on the opposite side, which is in contact with the container outer tank 2, is a laminated film. Is a material coated with aluminum by evaporation. Alternatively, the protective layer on the side in contact with the powder heat insulating material 7 of the vacuum heat insulating material 9 has a multiplex structure, and the protective layer on the opposite side, which is in contact with the container outer tank 2, has a single structure.

  Thereby, the low-temperature embrittlement resistance of the jacket material 12 on the side where the temperature of the vacuum heat insulating material 9 becomes low can be further increased. Thereby, low-temperature embrittlement can be suppressed efficiently, and the outer cover material 12 on the opposite side can be composed of a relatively inexpensive material or a small amount of the same material, thereby reducing the cost and reliability. Can be improved.

  In addition, the aluminum vapor deposition film located on the outer wall side has higher heat insulation performance than aluminum foil, so it is possible to suppress the entry of heat from the outside air, and it is possible to maintain the inside of the tank at a lower temperature. Become.

(Third embodiment)
Next, a third embodiment of the present invention will be described.

  FIG. 8 is a sectional view showing a heat insulating structure of a heat insulating container according to the third embodiment of the present invention.

  In the heat insulating structure of the present embodiment, the powder heat insulating material 7 of the first heat insulating box 5 and the second heat insulating box 8 in the first embodiment is constituted by a heat insulating panel 21 such as styrene foam. .

  In the present embodiment, the heat insulating panel 21 is formed of polystyrene foam, but is formed of a polyurethane foam, a phenol foam, and a heat insulating material selected from glass wool, perlite, and the like loaded in a heat insulating frame (not shown). May be.

  In addition, a gap between the heat insulating panels 21 and a gap between the vacuum heat insulating materials 9 are filled with a filling heat insulating material 22 to secure heat insulating properties. The filled heat insulating material 22 is made of a material that is close to the linear expansion coefficient of the container inner tank 3, such as phenol foam and polyurethane, which are soft and stretchable, and have a fiber diameter of less than 1 μm, such as microglass wool and soft urethane. Materials selected from foams and the like are used.

Further, the vacuum heat insulating material 9 is arranged so as to cover the entire surface of the first heat insulating layer formed of the heat insulating panel 21 with its outer peripheral edges abutting against each other. Further, in the present embodiment, the butt portion of the vacuum heat insulating material 9 is set to be shifted from the butt portion of the heat insulating panel 21 constituting the first heat insulating layer. Further, the sealing fin 17 formed on the outer peripheral edge of the vacuum heat insulating material 9 is disposed so as to be folded toward the low temperature side, that is, the heat insulating panel 21 side.

  Also in the heat insulating structure of the present embodiment, the vacuum heat insulating material 9 is adhered and fixed to the outer tank 2 side, and the same operation and effect as in the first embodiment can be obtained.

  Further, in the case of the present embodiment, a heat insulating layer that insulates between the container inner tank 3 and the vacuum heat insulating material 9 is formed by the heat insulating panel 21 on the container inner tank 3 side and the heat insulating panel 21 on the container outer tank 2 side. Are provided separately. The intermediate tank 4 is located between the heat insulating panel 21 on the container inner tank 3 side and the heat insulating panel 21 on the container outer tank 2 side, and the heat insulating panel 21 on the container inner tank 3 and the heat insulating panel 21 on the container outer tank 2 side. Material continuity with the panel 21 (continuity when the heat insulating panel 21 on the container inner tank 3 side and the heat insulating panel 21 on the container outer tank 2 side are connected to the vacuum heat insulating material 9 and are continuous. ) Has been severed. Thereby, the amount of leakage at ultra-low temperature can be reduced, and low-temperature embrittlement of the jacket material 12 of the vacuum heat insulating material 9 can be more effectively suppressed.

  Further, also in the heat insulating structure of the present embodiment, the thermal conductivity λ of the vacuum heat insulating material 9 is about 15 times lower than that of the heat insulating panel 21 made of styrene foam, as described above. Therefore, the heat insulation performance of the vacuum heat insulating material 9 can be remarkably improved as compared with the configuration including only the heat insulation panel 21 by the heat insulation by the heat insulation material 9.

  Furthermore, the vacuum heat insulating material 9 makes full use of its high heat insulating performance to shut off outside heat, and significantly reduces the ambient temperature inside the vacuum heat insulating material 9, that is, the portion where the plurality of heat insulating panels 21 are provided. Has been lowered. Thereby, the heat insulation effect of the multi-layer heat insulation panel 21 itself is relatively improved, and the heat insulation performance of the vacuum heat insulation material 9 itself is extremely high in combination with the high heat insulation effect exhibited by the vacuum heat insulation material 9 itself. be able to.

  Further, in the present embodiment, the vacuum heat insulating material 9 is abutted at a position shifted from the panel abutting portion of the heat insulating panel 21 to cover almost the entire outside of the heat insulating panel 21. Thereby, it is possible to prevent the low heat of LNG from moving to the outside air through the butted portion of the vacuum heat insulating material 9 through the gap between the butted portions of the heat insulating panel 21.

  Further, the sealing fin 17 of the vacuum heat insulating material 9 is configured to be folded into the heat insulating panel 21 side. This makes it possible to suppress a heat leak generated through the sealing fin 17 of the vacuum heat insulating material 9. Therefore, it is possible to efficiently exhibit the heat insulating effect that makes full use of the heat insulating effect of the vacuum heat insulating material 9 and the effect of lowering the ambient temperature at the portion where the heat insulating panel 21 is installed. Therefore, the heat insulating effect using the vacuum heat insulating material 9 can be sufficiently exhibited, and the heat insulating property can be significantly improved.

  The micro-glass wool of the filled heat insulating material 22 filled in the butted portions of the vacuum heat insulating materials 9 is flexible and highly stretchable. Therefore, even if the vacuum heat insulating material 9 expands and contracts according to the temperature of the outside air, the filling heat insulating material 22 expands and contracts accordingly. Thereby, cracking, tearing, and the like of the jacket material 12 due to restraining expansion and contraction of the vacuum heat insulating material 9 can be prevented, and high heat insulating performance can be secured for a long period of time.

  Further, in the configuration of the present embodiment, the vacuum heat insulating materials 9 are fixed by the filled heat insulating material 22. Therefore, cracks and the like are likely to occur due to stress distortion caused by a temperature difference between the upper and lower surfaces. Therefore, a configuration in which the thermal stress dispersing layer 18 is provided between the vacuum heat insulating material 9 and the heat insulating panel 21 to disperse the thermal stress is particularly effective.

  In addition, the intermediate tank 4 and the container inner tank 3 described in each embodiment are formed of a membrane or an invar. Since these members are resistant to thermal shrinkage, thermal shrinkage or overload is applied to the inner tank 3 and the intermediate tank 4 due to a change in the use environment, etc., and a low-temperature substance in the inner tank 3 such as LNG Can be prevented from leaking from the inner tank 3. Therefore, the leaked evaporative gas such as liquefied natural gas does not diffuse to the first heat insulating layer and the second heat insulating layer to impair the heat insulating performance, realizing a highly reliable heat insulating container. can do.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described.

  In the fourth embodiment, when the residual gas expands inside the jacket material 12 of the vacuum heat insulating material 9, it is possible to more reliably suppress and prevent rapid deformation of the vacuum heat insulating material 9. Like that.

  In the present embodiment, as shown in FIG. 9A and FIG. 9B, when the residual gas expands inside the jacket material 12 of the vacuum heat insulating material 9 and the residual gas exceeds a predetermined pressure, the residual gas is The explosion-proof structure A which releases the gas is provided to prevent the heat insulating container 1 from being damaged due to sudden abnormal deformation of the vacuum heat insulating material 9 and to enhance the safety.

  The configuration and effects of the parts other than the explosion-proof structure A are the same as those of the first to third embodiments, and are the same as those of the first to third embodiments. Are denoted by the same reference numerals, description thereof will be omitted, and only different portions will be described.

The explosion-proof structure A used in the present embodiment is not limited to a specific structure, but typically includes, for example,
Configuration Example 1: A configuration in which a jacket material 12 allows residual gas to escape to the outside to reduce expansion, and
Configuration Example 2: The adsorbent 16 enclosed together with the core material 11 inside the outer cover material 12 is of a chemisorption type that chemically adsorbs residual gas, or is non-exothermic that does not generate heat by adsorbing the residual gas. Or a chemisorption and non-pyrogenic composition,
Etc. are exemplified.

  An example of the explosion-proof structure A of Configuration Example 1 will be described with reference to FIGS. 9A and 9B.

  9A and 9B are diagrams illustrating an example of the configuration of the explosion-proof structure A according to the fourth embodiment of the present invention.

  Representative examples of the explosion-proof structure A of the configuration example 1 include a check valve 24 and a reduced strength portion 26 as shown in FIGS. 9A and 9B, respectively.

  FIG. 9A shows an example of the explosion-proof structure A constituted by the check valve 24. The check valve 24 has a cap-like configuration that closes a valve hole 25 provided in a part of the jacket material 12. The valve hole 25 is provided so as to penetrate the inside and outside of the jacket material 12, and the cap-shaped check valve 24 is made of an elastic material such as rubber.

  Normally, since the valve hole 25 is closed by the check valve 24, it is substantially prevented that outside air enters the inside of the jacket material 12. Even if the outer jacket material 12 contracts due to a change in ambient temperature and the inner diameter of the valve hole 25 changes accordingly, the check valve 24 is made of an elastic material. Can be closed. If the residual gas expands inside the jacket material 12, the check valve 24 easily comes off from the valve hole 25 as the internal pressure increases, and the residual gas escapes to the outside.

  FIG. 9B shows an example of the explosion-proof structure A configured by providing the reduced strength portion 26. The reduced strength portion 26 is configured by a portion 26a in which a part of the welding area is reduced in the welding portion between the sealing fins 17.

  In the example of the reduced strength portion 26, the inside (the core 11 side) of the welding portion 26a of the sealing fin 17 is not welded. For this reason, the welding area at the portion 26a is smaller than the welding portion of the other sealing fins 17, and in the event that the residual gas expands inside the jacket material 12, the pressure due to the increase in the internal pressure is reduced. It is easy to concentrate on the weakened portion 26. Then, the portion 26a of the heat welding layer 15 having a reduced welding area is peeled off, and the residual gas is released to the outside.

  Note that the strength-reducing portion 26 is not limited to the configuration shown in FIG. 9B in which the welding area is partially reduced, and may have a configuration in which the welding area is the same or the welding strength is partially reduced. For example, when the sealing fin 17 is heat-welded, the heat applied to only a part of the sealing fin 17 may be reduced to weaken the degree of welding at the welding site. Alternatively, the reduced strength portion 26 may be provided at a position other than the welding portion of the sealing fin 17. For example, a portion where the lamination strength is partially reduced may be formed between the heat-welding layer 15 and the gas barrier layer 14 that forms the outer covering material 12 to form the strength-reduced portion 26.

  Further, the strength-reduced portion 26 may be formed by changing a part of the material of the heat-welding layer 15 to a material having lower welding strength than other portions. For example, as described above, low-density polyethylene can be suitably used as the heat-welding layer 15, but high-density polyethylene, ethylene-vinyl alcohol copolymer, or amorphous polyethylene Terephthalate or the like may be used. Since these polymer materials have lower welding strength than low-density polyethylene, they can be suitably used for forming the strength-reduced portion 26.

  Further, as a method of forming the reduced strength portion 26, a configuration in which the thickness of the welded portion between the heat welding layers 15 is partially reduced, and an adhesive having a small adhesive strength is applied to a part of the region to be the welded portion of the heat welded layer 15. And a configuration in which the heat-welding layer 15 is partially peeled off in the region of the outer cover material 12 to be the sealing fin 17 so that the gas barrier layers 14 are directly heat-welded to each other. .

  If an accident or the like occurs, the vacuum heat insulating material 9 may be exposed to a severe environment. However, in the case of the present embodiment, when the vacuum heat insulating material 9 is exposed to a severe environment and the residual gas inside expands or the like, the check valve 24 comes off from the valve hole 25 or excessively expands from the weakened portion 26. It is possible to effectively avoid deformation of the vacuum heat insulating material 9 due to pressure being dissipated to the outside. Therefore, the explosion-proof property of the vacuum heat insulating material 9 can be improved, and the safety of the heat insulating container 1 can be improved.

  9A and 9B showing the configuration of the present embodiment, the explosion-proof structure A is highlighted without showing the thermal stress dispersion layer 18 provided on the vacuum heat insulating material 9.

  On the other hand, as the explosion-proof structure A of the configuration example 2, there is an adsorbent composed of the ZSM-5 type zeolite described above. ZSM-5 type zeolite constituting the adsorbent is a gas adsorbent having a chemical adsorption action. Therefore, even if various environmental factors such as a rise in temperature occur, the gas once adsorbed is substantially prevented from being released again. Therefore, even when the combustible fuel or the like is handled, even if the adsorbent 16 adsorbs the combustible gas due to some influence, the gas is not re-discharged due to a subsequent temperature rise or the like. As a result, the explosion-proof property of the vacuum heat insulating material 9 can be further improved.

  In addition, since ZSM-5 type zeolite is a non-combustible gas adsorbent, the adsorbent 16 in the present embodiment is substantially composed of only a non-combustible material. Therefore, the explosion-proof property can be further improved without using a flammable material inside the vacuum heat insulating material 9 including the core material 11.

  As described above, if the adsorbent 16 is a chemisorption type, the adsorbed residual gas is not easily released compared to the physical adsorption type, so that the degree of vacuum inside the vacuum heat insulating material 9 can be maintained well. it can. In addition, since the residual gas is not desorbed, the risk that the residual gas expands inside the outer cover material 12 and the vacuum heat insulating material 9 is deformed can be effectively prevented. Therefore, the explosion-proof property and stability of the vacuum heat insulating material 9 can be improved.

  If the adsorbent 16 is a non-heat-generating material, a non-combustible material, or a material that satisfies both of them, foreign substances enter the inside due to damage to the jacket material 12 or the like. Also, it is possible to avoid the possibility that the adsorbent 16 generates heat or burns. Therefore, the explosion-proof property and stability of the vacuum heat insulating material 9 can be further improved.

  As described above, the heat insulating container 1 according to the embodiment of the present invention can ensure high heat insulating performance over a long period of time while achieving cost reduction. However, it is needless to say that the configuration can be variously changed within a range that achieves the object of the present invention.

  For example, the thermal stress dispersing layer 18 is illustrated as being provided on both surfaces of the vacuum heat insulating material 9, but it is sufficient that the thermal stress dispersing layer 18 be provided on at least one surface serving as an adhesive surface to a heat insulating box or the like. In this case, the effect of improving the strength of the upper and lower surfaces of the vacuum heat insulating material 9 and preventing the reduction of quality defects cannot be expected, but achieves the purpose of preventing cracks against the heat shrinkage stress of the vacuum heat insulating material 9. Is enough.

  Although the glass cloth is illustrated as the thermal stress dispersion layer 18, any material may be used as long as it can disperse the tensile contraction force due to the thermal contraction of a heat insulating box or the like. For example, in addition to glass fiber, a material selected from carbon fiber, alumina fiber, silicon carbide fiber, aramid fiber, polyamide fiber and polyimide fiber having a small linear expansion coefficient and relatively high strength can be used.

  Further, the thermal stress dispersion layer 18 is exemplified by a material that is laminated on the outer cover material 12 of the vacuum heat insulating material 9 and constitutes the outermost layer of the outer cover material 12, but the thermal stress dispersion layer 18 is a single component. Alternatively, the adhesive may be bonded and integrated to both the vacuum heat insulating material 9 and the second heat insulating box 8.

  Further, in the embodiment, the example in which the heat insulating container 1 is used as a tank of an LNG transport ship or the like is shown, but the present invention is not limited to this example, and the heat insulating container such as an LNG tank installed on land, or a medical device. It may be an insulated container such as a low-temperature storage container used for industrial and industrial purposes. The substance to be stored is not LNG, but may be any substance such as liquid hydrogen, which is lower than normal temperature by 100 ° C. or more.

  As described above, the heat-insulating container according to the embodiment of the present invention is a heat-insulating container that holds a substance that is at least 100 ° C. lower than room temperature, and includes an inner tank 3, an outer tank 2, and an inner tank 3. Insulating boxes 5 and 8 provided between the container and the outer tank 2, and insulating layers 7 and 9 provided inside the insulating boxes 5 and 8. The heat-insulating layer includes a panel-shaped vacuum heat-insulating material 9 having a core material 11 and a jacket material 12 for vacuum-sealing the core material 11, and a heat-insulating material 7 made of a material different from the vacuum heat-insulating material 9. have. The vacuum heat insulating material has a configuration in which it has a thermal stress dispersion layer 18 and is fixed to a heat insulating box.

  This makes it possible to use a general-purpose panel-shaped vacuum insulation material to ensure insulative properties at low cost, and even if the insulation material in the insulation box becomes thin and there is a play gap, the vacuum insulation material can be used. Micro-vibration in the heat-insulating box is eliminated, and a decrease in heat-insulating properties due to damage to the covering material can be prevented. Therefore, it is possible to prevent a decrease in heat insulation performance due to damage to the outer cover material of the vacuum heat insulation material, and to ensure high heat insulation over a long period of time at low cost.

  Further, the heat insulating material may be provided on the container inner tank side of the heat insulating box, and the vacuum heat insulating material may be provided on the container outer tank side of the heat insulating material outside the heat insulating material.

  According to such a configuration, the ultra-low temperature leaking from the ultra-low temperature substance to the vacuum heat insulating material is further reduced by the heat insulating effect of the heat insulating material, and the outer material can be suppressed from being low-temperature embrittlement. Therefore, it is possible to suppress a decrease in heat insulation performance due to damage to the jacket material due to low-temperature embrittlement of the vacuum heat insulation material, and to ensure high heat insulation over a long period of time.

  Further, the vacuum heat insulating material may be integrally bonded and fixed to the inner surface of the heat insulating box via a thermal stress dispersion layer.

  According to such a configuration, further, the thermal expansion coefficient of the insulating box and the thermal insulation coefficient of the vacuum thermal insulating material are different, and a thermal contraction difference occurs between the thermal insulating box and the vacuum thermal insulating material, Even if the heat-shrinking force of the primary heat-insulating layer is applied to the jacket material of the vacuum heat-insulating material, the heat-shrinking force is dispersed by the heat-stress-dispersing layer. In addition, the outer cover material of the vacuum heat insulating material is suppressed from generating cracks and the like due to the difference in heat shrinkage. Thereby, even if the vacuum heat insulating material is fixed to the heat insulating box, the original high heat insulating performance can be maintained as it is, and the heat insulating performance of the heat insulating container can be satisfactorily secured for a long period of time.

  Further, the thermal stress dispersion layer may be configured by a glass cloth.

  According to such a configuration, the heat insulation performance of the glass cloth is further added, and at the same time, the heat shrinkage crack of the jacket material is prevented, and at the same time, the heat insulating property of the jacket material itself is improved, and the low temperature embrittlement of the jacket material itself is reduced. Can be suppressed. Therefore, it is possible to enhance reliability and further ensure high heat insulation for a long period of time.

  Further, the vacuum heat insulating material may have a configuration in which a thermal stress dispersion layer is integrally laminated on at least a surface of the outer cover material that is in contact with the inner surface of the heat insulating box.

  According to such a configuration, the amount of glass cloth that causes a cost increase can be further reduced by using only one surface on the inner surface side of the heat insulating box. Therefore, it is possible to satisfactorily guarantee the heat insulation performance over a long period of time while suppressing an increase in cost.

  Further, the vacuum heat insulating material may have a configuration in which a thermal stress dispersion layer is integrally laminated on the upper and lower surfaces of the outer cover material, and an outermost layer of the outer cover material is formed.

  According to such a configuration, further, since the outermost layers on the upper and lower surfaces of the vacuum heat insulating material become high-strength thermal stress dispersion layers, the outer material is cracked or broken by handling during production. Can be prevented. Therefore, it is possible to suppress the defective product occurrence rate of the vacuum heat insulating material, suppress the cost increase, and satisfactorily guarantee the heat insulating performance of the heat insulating container over a long period of time.

Further, as the core material of the vacuum heat insulating material, it may be configured to have use of inorganic fibers.

  According to such a configuration, even if moisture remains in the jacket material of the vacuum heat insulating material, the core material is expanded by the moisture, and the deformation of the vacuum heat insulating material itself can be suppressed. . For example, when maintenance such as washing with hot water is performed periodically, as in the case of a heat insulating container for an LNG transport ship, the vacuum heat insulating material may expand and deform even if some moisture remains in the outer cover material. Can be prevented, and the occurrence of cracks in the jacket material due to thermal expansion deformation of the vacuum heat insulating material itself can be prevented. Therefore, the insulation performance can be ensured more reliably.

  Further, the vacuum heat insulating material may have a configuration having an explosion-proof structure.

  According to such a configuration, even if a slight amount of moisture or air remains in the vacuum heat insulating material and expansion may occur due to the humidity or air, if the expansion pressure becomes a predetermined value or more. In addition, the expansion pressure can be discharged to the outside from the explosion-proof structure. Therefore, it is possible to prevent the explosive destruction from occurring by continuing to expand as it is, thereby ensuring safety.

  Further, the heat insulating box has a first heat insulating box 5 having a heat insulating material 7, a heat insulating material 7 disposed on the container inner tank side, and a vacuum heat insulating material 9 disposed on the container outer tank side outside the heat insulating material 7. And a second heat insulation box 8. Then, the first heat insulating box may be arranged on the container inner tank side, and the second heat insulating box may be configured such that the vacuum heat insulating material is arranged on the container outer tank side.

  According to such a configuration, further, the ultra-low temperature leaking from the substance stored in the container inner tank to the vacuum heat insulating material is caused by the double heat of the heat insulating material of the first heat insulating box and the heat insulating material of the second heat insulating box. And the low-temperature embrittlement of the jacket material can be more strongly suppressed. As a result, the vacuum heat insulating material can more reliably prevent the heat insulating performance from being impaired due to the occurrence of cracks in the jacket material. Therefore, high heat insulation can be ensured for a longer period.

  Further, the heat insulation box arranged on the container outer tank side has a box frame body having an open surface, and a partition body provided in the box frame body to partition the inside of the heat insulation box. And it is unitized by the vacuum heat insulating material laid on the bottom surface of the section partitioned by the partition body, the heat insulating material arranged on the opening side of the vacuum heat insulating material, and the closing plate closing the opening side of the box frame. May be adopted.

  According to such a configuration, the heat insulating material and the vacuum heat insulating material can be easily loaded between the inner vessel and the outer vessel simply by loading the heat insulating box. Accordingly, the transportability is improved, the productivity of the tank is improved, and the low-temperature embrittlement of the vacuum heat insulating material can be prevented with a simple configuration, and high heat insulating properties can be ensured for a long period of time.

  Further, the heat insulating material may be a structure formed of a powder heat insulating material or a heat insulating panel.

  According to such a configuration, for example, perlite, and a heat insulating panel such as styrene foam or urethane foam, and a panel-shaped vacuum heat insulating material are distributed as general-purpose parts, so that they can be obtained at low cost. it can. And, in the case of the heat insulating panel, since it has a panel shape like the vacuum heat insulating material, it can be easily loaded simply by laying it. In addition, when powder heat insulating material is not used, equipment that prevents powder from rising is not required, and a simple structure prevents low-temperature embrittlement of vacuum heat insulating material, and ensures high heat insulating properties over a long period of time. Can be guaranteed throughout.

  Further, the vacuum heat insulating material may have a sealing fin of the jacket material, and the sealing fin may be configured to be folded toward the heat insulating material.

  According to such a configuration, it is possible to further prevent the sealing fin specific to the panel-shaped vacuum heat insulating material from coming into contact with the outer vessel of the container and transferring heat through the outer casing material such as a laminate film. Therefore, high heat insulation performance can be maintained.

  Further, the heat insulating structure according to the embodiment of the present invention is a heat insulating structure provided with an outer vessel, a first heat insulating box, and a second heat insulating box. The first heat-insulating box has a first box frame, a first heat-insulating material provided in the first box frame, and a first blockage closing the opening side of the first box frame. It is unitized by a plate. The second heat-insulating box is provided on the second box frame, a partition provided in the second box frame, and partitioning the inside of the second heat-insulating box, and laid on a bottom surface of a section partitioned by the partition. And a second heat insulating material disposed on the opening side of the vacuum heat insulating material, and a second closing plate closing the opening side of the second box frame. The second heat insulating box is disposed closer to the outer tank than the first heat insulating box, and the vacuum heat insulating material has a thermal stress dispersion layer and is fixed to the second closing plate.

  This makes it possible to use a general-purpose panel-shaped vacuum insulation material to ensure insulative properties at low cost, and even if the insulation material in the insulation box becomes thin and there is a play gap, the vacuum insulation material can be used. Micro-vibration in the heat-insulating box is eliminated, and a decrease in heat-insulating properties due to damage to the covering material can be prevented. Therefore, it is possible to prevent a decrease in heat insulation performance due to damage to the outer cover material of the vacuum heat insulation material, and to ensure high heat insulation over a long period of time at low cost.

  INDUSTRIAL APPLICABILITY As described above, the present invention can ensure high heat insulating performance at a low cost over a long period of time and can be widely applied as a heat insulating container for storing and transporting cryogenic substances such as LNG.

DESCRIPTION OF SYMBOLS 1 Insulated container 2 Container outer tank 3 Container inner tank 4 Intermediate tank 5 First heat insulating box 6 Box frame 7 Powder heat insulating material (first heat insulating layer)
8 Second insulation box 9 Vacuum insulation (second insulation layer)
DESCRIPTION OF SYMBOLS 10 Closure plate 11 Core material 12 Outer cover material 13a 1st protective layer 13b 2nd protective layer 14 Gas barrier layer 15 Heat welding layer 16 Adsorbent 17 Sealing fin 18 Thermal stress dispersion layer 21 Heat insulation panel 22 Filling heat insulating material 24 Check valve 25 Valve hole 26 Part of reduced strength A Explosion-proof structure

Claims (11)

An insulated container holding a substance at least 100 ° C. lower than room temperature,
A tank in the container,
An outer tank,
An insulating box provided between the container inner tank and the container outer tank,
A heat insulating layer provided inside the heat insulating box,
The heat insulating layer has a core material and a jacket material for vacuum-sealing the core material, a panel-shaped vacuum heat insulating material, and a heat insulating material made of a material different from the vacuum heat insulating material. ,
The heat insulating material is disposed on the inner tank side of the heat insulating box,
The vacuum heat insulating material is disposed on the container outer tank side outside the heat insulating material of the heat insulating box,
A heat insulating container, wherein the vacuum heat insulating material has a thermal stress dispersion layer made of glass cloth and is fixed to the heat insulating box.
The heat insulating container according to claim 1, wherein the vacuum heat insulating material is integrally bonded and fixed to an inner surface of the heat insulating box via the thermal stress dispersion layer.
The heat insulating container according to claim 2, wherein the vacuum heat insulating material is such that the thermal stress dispersion layer is integrally laminated on at least a surface of the outer cover material that is in contact with the inner surface of the heat insulating box.
4. The heat insulating container according to claim 2 , wherein the vacuum heat insulating material is formed by integrally laminating the thermal stress dispersion layer on both upper and lower surfaces of the outer cover material to form an outermost layer of the outer cover material. 5.
The heat insulating container according to any one of claims 1 to 4 , wherein an inorganic fiber is used as the core material of the vacuum heat insulating material.
The heat insulating container according to any one of claims 1 to 5 , wherein the vacuum heat insulating material has a configuration having an explosion-proof structure.
The insulation box is
A first heat insulation box having the heat insulation material;
A second heat insulating box in which the heat insulating material is arranged on the container inner tank side and the vacuum heat insulating material is arranged on the container outer tank side outside the heat insulating material;
The said 1st heat insulation box is arrange | positioned at the said container inner tank side, and the said 2nd heat insulation box was arrange | positioned so that the said vacuum heat insulating material might be located at the said container outer tank side. 7. The heat-insulating container according to any one of 6 .
Before Symbol the second of the insulating box,
A box frame with one side open,
Having a partition body provided in the box frame body to partition the inside of the heat insulating box,
The vacuum heat insulating material laid on the bottom surface of the partition partitioned by the partition body, the heat insulating material disposed on the opening side of the vacuum heat insulating material, and a closing plate closing the opening side of the box frame. The heat insulating container according to claim 7, which is unitized by the following.
The heat insulating container according to any one of claims 1 to 8 , wherein the heat insulating material is a powder heat insulating material or a heat insulating panel.
The vacuum heat insulating material has a sealing fin of the jacket material,
The heat insulating container according to any one of claims 1 to 9 , wherein the sealing fin is formed by being folded toward the heat insulating material.
A heat insulating structure comprising a container outer tank, a first heat insulating box, and a second heat insulating box,
The first heat-insulating box includes a first box frame, a first heat-insulating material provided in the first box frame, and a first box-frame closing an opening side of the first box frame. Unitized by a closing plate,
The second heat insulating box is provided with a second box frame, a partition member provided in the second box frame, and partitioning the inside of the second heat insulating box, and a bottom surface of a partition partitioned by the partition member. A second heat insulating material disposed on the opening side of the vacuum heat insulating material, and a second closing plate closing the opening side of the second box frame. ,
The second heat insulation box is disposed closer to the outer container than the first heat insulation box,
A heat insulating structure , wherein the vacuum heat insulating material has a thermal stress distribution layer made of glass cloth and is fixed to the second closing plate.